
package com.zhao.until;

import com.netflix.client.config.IClientConfig;
import com.netflix.loadbalancer.AbstractLoadBalancerRule;
import com.netflix.loadbalancer.ILoadBalancer;
import com.netflix.loadbalancer.Server;

import java.util.List;
import java.util.concurrent.ThreadLocalRandom;

public class ZhaoRandomRule extends AbstractLoadBalancerRule {

    //每个服务访问5个，换下一个服务
    //total = 0 ;默认=0,如果等于5，我们指到下一个节点
    // index = 0;默认=0，如果total =5;index+1

    private int total = 0; //被调用的次数
    private int currentIndex = 0; //当前谁在提供服务

    @SuppressWarnings({"RCN_REDUNDANT_NULLCHECK_OF_NULL_VALUE"})
    public Server choose(ILoadBalancer lb, Object key) {
        if (lb == null) {
            return null;
        } else {
            Server server = null;

            while(server == null) {
                if (Thread.interrupted()) {
                    return null;
                }
                //获得活着的服务
                List<Server> upList = lb.getReachableServers();
                //获得全部的服务
                List<Server> allList = lb.getAllServers();
                int serverCount = allList.size();
                if (serverCount == 0) {
                    return null;
                }
//                //生成区间随机数
//                int index = this.chooseRandomInt(serverCount);
//                //从活着的服务中，随机取一个服务
//                server = (Server)upList.get(index);
                if(total<5){
                    server = upList.get(currentIndex);
                    total++;
                }
               else{
                   total = 0;
                   currentIndex++;
                   if(currentIndex>upList.size()){
                       currentIndex = 0;
                   }
                   server = upList.get(currentIndex); //从活着的服务中，获取指定的服务来进行操作
                }

                if (server == null) {
                    Thread.yield();
                } else {
                    if (server.isAlive()) {
                        return server;
                    }
                    server = null;
                    Thread.yield();
                }
            }
            return server;
        }
    }

    protected int chooseRandomInt(int serverCount) {
        return ThreadLocalRandom.current().nextInt(serverCount);
    }
   @Override
    public Server choose(Object key) {
        return this.choose(this.getLoadBalancer(), key);
    }
   @Override
    public void initWithNiwsConfig(IClientConfig clientConfig) {
    }
}
